Exciting Implications of Century-Long Soil Study

World Soil Day falls on December 7th and it has the importance of soil as a lifeblood of horticulture and the planet on our minds.  In this week's blog post we look at a monumental 100 year-long study into soil health, and the promising findings it's made regarding how growers can improve their soil health and yields, and how organic growers in particular can match conventional yields.  We'll also look at how the study has highlighted the need to bridge the gap between scientific studies and practical application.  Finally, we'll discuss how Croptracker helps growers conduct their own longitudinal studies, helping them get the most out of experimental trials and make more informed decisions for their operations.

Researchers at UC Davis are beginning the 25th year of a planned century-long study of how conventional and organic management practices change the soil over time.  For researchers at the several study sites nationwide, soil health is at the top of the priority list.

“We have neglected soil health for many years,” says Kate Scow, UC Davis soil microbial biologist and director of Russell Ranch, one of UC Davis's nationwide research sites in Winters, California.  “There are indications you can look for in your field, and we are also taking measurements you can only do in a laboratory.”

Researchers presented findings at Russell Ranch Field Day 2018: Increasing Farm Resilience Through Healthy Soils and Water Management.  

As presented at the field day, the study has revealed how common soil-quality metrics fail to address the organisms that live within it.  One such metric is the Storie Index, a method of soil rating developed in the 1930s which measures soil depth and texture, soil permeability, soil chemical characteristics, drainage, surface runoff, and climate.  However, the UC Davis study has disputed the legitimacy of the index as a true test of soil health.  "We have a field with soil that is 100 on the Storie Index, which is as good as it can be,” says grower Rich Collins of Collins Farm in Davis, California. “But it was 100 when we got it, and it was dead.”

Results from the 25-year progress (so, in this century-long study's case, "early results") indicate that a program of treating the soil with cover crops and composted poultry manure can enhance the life of the soil.  “The organic treatment has the highest score on biological indicators of soil health," says Scow.

Researchers even discovered that this treatment program can produce organic yields of some crops that match nearby conventional plots.

“Unlike the literature that says organic yields are 15 to 20 percent lower, our organic tomato yields were not lower,” said Nicole Tautges, UC Davis Russell Ranch cropping systems researcher. “We see a positive yield response to cover crops. We saw an increase in tomatoes in two or three years; with corn, it took seven or eight.”

The field day discussion highlighted a need for greater applicability of academic trials to production in a competitive commercial environment.  After all, in the practical world, it is not always viable to let the soil take time off from production long enough to benefit from cover crops.  To compound this, researchers are finding that the practices that build long-term soil resiliency may not pay off in better yields or crop quality the first year or two - meaning growers have a long wait to see if experimental programs will even benefit them at all.  “When I hear a scientist trying something on a small plot that’s working great, I’m not going to go out and try it on 100 acres,” commented one grower at the field day. “When my neighbor does something next door, I pay attention to it."

The study discussed today reflects a growing understanding of the importance of soil health to horticulture, and it's exciting to think what the study will uncover in the next 75 years.  In the meantime, steps should be taken to build the connection between academia and practical application.  Closer collaboration between scientists and growers, more trials conducted on real farms rather than testing sites, and more funding to help growers mitigate the risk of implementing experimental programs may help bridge the gap.

Meanwhile, growers may want to conduct their own longitudinal studies to assess the efficacy of experimental programs by tracking changes in yields.  In the past, this would have been a strenous effort; with hand-drawn calculations and scores of paperwork and notes to dig out of storage and make sense of.  Today, crop management software like Croptracker lets growers easily accumulate, store, and view long-term data.  Capable of generating over 50 reports, Croptracker can make sense of years of records instantaneously and let growers track trends over time.  This lets growers accurately assess how different management practices have affected their results and make more informed decisions for their farm.

As mentioned above, results of scientific studies conducted in one geographical area cannot be assumed to be generalizable to every farm.  If growers have the tools to conduct their own longitudinal studies, they can test-drive new management practices, understand how their yields are affected, and determine if the program is worth continuing. 

Need a refresher on any of Croptracker's features? Head over to our Knowledge Base, where you'll find step-by-step tutorials as well as common troubleshooting tips and more.  And as always, if you're ever stuck, never hesitate to e-mail us at support@croptracker.com or Live Chat with us by clicking the green speech bubble  in your bottom right-hand corner.  We're always happy to help you let Croptracker make your farm become more efficient, safe, and profitable!